7Li, C. N. & S. A. Thompson. 1976. Subject and topic: a new typology of language [ A ]. In C. Li (ed.). Subject and Topic [ C]. New York: Academic Press. Pp. 457-498.
8Keenan, A. & B. Comrie. 1977. Noun phrase accessibility and universal granmar [ J ]. Linguistic Inquiry 8: 63-99.
9van Hoek, K. 1997. Anaphora and Conceptual Structure [ M ]. Chicago: The University of Chicago Press.
